Double-barreled machine gun with recoiling barrels



5 Sheets-Sheet 1.

C. GAST Filed Sent.y 30.

DOUBLE BARRELED MACHINE GUN WITH RECOILIYNG BARREIJSk Dec.. 11 1923o 5 Sheets-Sheet 2 per Dec. 11 1923., @GAST DoBLE BARRELED MACHINE GUN WITH REcoILING ARnELs Filed Sebi. 50. 1920 Dec. 1l 1923.

C. GAST DOUBLE BARRELED MACHINE GUN WITH REcoxLING BARRELS Filed sm. So, 1920 5 sheets-,sheet 3 vwefntov' l er (MRL EAST, T HfmA Attorney.

y Dec. 11 111123.., 1,477,115

C. GAST DOUBLE BARRELED MACHINE GUN WITH BEGOILING BARRELS Filed Sent. 50, 1920 5 Sheets-Sheet 4 i- IGL lIn'mmtor:

MRL GAST, er

Attorney.

IGJQ@ 46, AIF-|6617. 3

"Dcl 11, 1923., 1,477,115

C. .GAST

DOUBLE BARRELED MACHINE GUN WITH RECOlLING BARRELS Filed SeDt. 30. 1920 5l Sheets-Sheet 5 Inventor: UAR/ GAS 7'.

Attorney. l

Patented Dec.` ll, 1923. i

UNITED STATE 1,411,115 OFFICE- CARL GAST, `O1? BARMEN, GERMANY.

l DOUBLE-BARRELED MCHIZNE GUN WITH-RJECOILNG BARRELS.

Application led September 30, 1920. Serial No. 413,@87.'

rThis invention relates to double-barreled.

machine guns of the recoiling barrel type. llhe object of the invention is to provide an improved means of tensioning vthe firing mechanism. l i

Another objectv of the] invention is to provide a recoiling mechanism in which no separate mechanism is required for tensioning the firing pin and in which the springs commonly used in guns of the type in question for advancing the breech block are dispensed with. y 4

IAnother object of the invention is to provide a mechanism for locking each breech block in contact with the breech end of its barrel in a more reliable and positive inanner than heretofore.

1n accordance with these objects the invention consists in combining in a doublebarreled machine gun two systems of recoiling breech and tiring mechanism, one system associated with each barrel, connections between the two systems whereby recoil of one produces advance of the other system, and means operating automatically during the advance of each system to cock the firing mechanism thereof.

The invention also consists in providing a breech locking mechanism comprising rotary locking discs mounted in each breech slide,

said discsbeing adapted when in one position to engage projecting cheeks of the breech block and lock the saine against the breech end of the barrel, and in another position to Aallow free movement of said cheeks past the discs, the discs being turned into and out of breech closing and locking position at suitable instants by means of fixed stops.

A constructional arrangement according to the present invention is illustrated by wayl of example inthe accompanying' drawings, in which-` Fig. 1 is a sectional elevation through the opened barrel system, the breech mechanism being in` tensioned condition.

Fig. 2 is asimilar section showing the breech mechanism in the fired position and just before the beginning of the recoil,

Fig.4 3 is a plan of the gun with a partial section through the receiver Fig. l is a rear view of t e gun,

Fig. 5 shows a plan and a side-elevation of the oscillating lever `for driving the two reciprocating chambers 6';

Fig. 6 shows a side-elevation and a plan of one of the pawls holding the breechblocks temporarily inv their advanced position;

Fig. 7 shows a side-elevation and a plan of one of the two spring-connected slidestop-levers;

Fig. 8 shows a front view, a side view and a plan of an impact member for taking up the recoil of the fired system;Y

Fig. 9 shows a vertical' transversal section through the receiver-casing and the twobarrel system, this section being taken at the place containing the breech-locking mechamsm;

Fig. 10 shows a side-elevation, a plan and a front-elevation of the breech-block;

Fig. 11 shows a front-elevation and a sideelevation ot a clamp,serving as an abutment for the tiring-pin spring;

Fig. 12 shows a front-elevation, a sideelevation and a plan of the firing-pin nut;

Fig. 13 shows elevations of the lockingdislr of the breech-locking mechanism, seen from three dierent sides.

Fig. 14: is a vertical section through the` breech slide showing breech locking mechanism in unlocked condition', Fig. 15 is a. corresponding sectional elevation through the receiver, the locking mechanism being in unlocked condition,

Fig. 16 is a section through a breech slide with the locking mechanism in unlocked condition,

Fig. 17 corresponds to Fig. 14 and shows the breech locking mechanismin locked condition, i

Fig. 18 corresponds to Fig. 15 and shows the breech locking mechanism in locked condition,

Fig. 19 Fig. 17,

LFigs. 20 and 21 show the head of the breech block with its cheeks or bosses in two views. l p

The gun comprises two barrel systems arranged alongside of each other in a Casing is a section 'on the line C`D oit' receiver.

of a collar 4* on the breech end of the barrel which is inserted from the top into a corresponding recess in the head 3 of the breech slide, so that the barrel can be readily exchanged. f On the bottom of the breech slide 3 there is provided a hollow enlargement 31 in which the breech spring 19 1`s contained, the free end of which spring abuts against an impact member 18 mounted on the guide block 17. On the bottom of the breech slide there is also pivoted a sear lever 13, acted upon by a spring and having one of its ends projecting through as slot 32- in the wall of the breech slide into the interior of this latter. This sear lever coo erates with the trigger rod 20, which is sllidably mounted in the bottom of the rel ceiver and is actuated by means of the tri- L ger' 21. When the rod 20 moves to the 1e (Figs. 1 and 2) an inclined lug 2O*l thereon engages the end 13 of the Sear lever 13'in lhinged to each breech slide. also a spring pressed so-called breech pawl 2.2, the front end of which holds the breech-block temorarily in advanced osition within the reech slide, whilst during the recoil of the breech slide an opposing incline on the casing 1 swings the front end of the breech "pawl away from the rear-end of the breechblock, so that the breech-block may swing back into its rear osition.

The breech bloc works inside the breech slide 3 and consists in the usual manner of a bore or chamber 6, a firing pin 7 therein controlled by a firing pin spring 8, a counter-spring 9, a firing pin nut 10, a clamp 11 serving as an abutment for the firing pin sprin 8 andhaving U-shaped limbs whlch strad le the firin pin, and-an extractor 12. The breech block 1s forked at its rear end and a pin 6" is mounted in the fork. The pins of the two breech blocks of the gun en ge forked ends of a driving lever 24-see i A3 andf-which extend through slots in t e breech slides 3 into the paths of the breech blocks. The lever 24 is rotatably supported b 'means of a ivot 34 on a block 28 on t e bottom of 4t e receiver. To the outer end of this pivot there isattached the loading handle 26, which latter is also connected with the lever 24 by means of screws 30.

The driving lever carries two release pins 25, which according to the osition of the lever act upon one or the ot er of two stop levers 23 pivoted on the guide block 17 of each breech, to turnthe stops out of the path of the breech slide, in Vwhich they are normally held b means of a tension spring s l 35 connecting t em. To each breech slide on its inner side there is attached a dog 27 .which lies in the plane of the lever 24,and

which on recoil of the breech slide throws over the lever. In its front part thebreech slide 3 is slotted through kto allow the insertion and ejection of thecartridges. Into thereby bring about the locking of the breech with the firing pin spring in tensioned condition in a manner described hereinafter. The locking discs are provided on the inner side with a slot 16 adapted to allow passage of the cheek `(6) on the breech block. The locking discs are also provided on the outer side with a recess having two striking faces 16c and 16b 'arranged opposite to each other but axially displaced-,see Fig. 13. These striking faces lie in the path of two correspondingly formed fixed abutments 15 and 15b on the block 15, Iwhich during the forwards and backwards stroke of the breech slide effect shifting of the lockingdiscs 16 into locking or releasing position by striking the contact face 16d or 16. l

The mode of operation of the gun is as follows:

By means of' the loadinr handle 26 the open breech block 6 (in ig. 3) is moved forwards into contact with the barrel. During part of the forward movement the firing pin spring 8k is tensioned by means of the clamp 11, the U-shaped limbs of which it abuts. Just before the breech block reaches the barrel, the release pin 25 .of the drivingk lever 24 strikes ,against the slide stop lever 23 .and swlngs it out in such a manner that it releases the slide', allowing this latter to be'urged forwards by the spring 19. Thel slots 16l of the locking discs 16-are in such a position up to the time that the release pins,

retraction of the levers 23,-the strikingfaces 16 of the *locking discs 16 meet the fixed abutments 15 of the blocks 1 5, whereby the discs '164 are rotated causing the eccentricy Mamie v rubbing. surfaces 16".` to engage the rear surfacesk 6d of the cheeks, and thereby arrest and -lock the breech block (Figs. 17219). The breech of this system is now closed in tensionedI condition and the gun ready to fire, while the breech of the. other system, on

E the contrary, is open.

To fire the gun, the trigger 21' is pulled. The trigger rod 20 which is common to both systems is thereby actuated and its inclined lugs 20l act uponthe end 1??,a of the sear lever 13 y,of the breech system which is in the forward position in such a manner that the end of the sear lever which extends into the ath of the firing pin nut l() is withdrawn.

he firing pin 7 is freeda and the iiring pin spring 8 urges the pin forwards against the end of the c artridge, so that the latter is fired. The position of the parts at this instant is shown in Fig. 2i The breech block -6, breech slide 3, and the fired barrel recoil at first-as a whole. Hence the pin 6b, the

extreme end of -thev lever 24,and the dog 27 have the same velocity oftranslation. The

p artof the lever 24lopposite the point or `tip of `the dog27, being much nearer the pivot than the extreme end of the lever, will move backward more slowly than the pin 6" and than the tip of the dog 27, whereby this tip will approach the adjacent part of the lever 24 as the parts recoil. The timingy is such that the tip of the dog 27 will strike the lever after the breechy block 6 has been unlocked from the slide 3 in a manner described hereunder. "The impact or' the dog on the lever 24 at a place near the pivot gives a greatly accelerated motion to the lever which is transmitted to .the breech block 6. The latter then begins to move backwards more rapidly than the slide while the other breech block 6 is correspondingly shot forwards.

7 The unlocking of the breech/'block 6 from the breech slide 3 is caused by the faces 16" of the locking discs 16 impacting upon the `fixed abutments l5", whereby the discs 16 are tur-ned and the slots 1.6a give free passage to the cheeks 6a of' the breech block (Figs.

11i-16). It is seen that one arm of the lever eration the spring immediately urges the slide forward again until the lever 23 again snaps into its recess 36 and thereby interi rupts the movement of the Slide and locks the same. The operation is repeated alternately in the/two systems and automatically, as just described, as long as the gunner holds back the trigger rod 20 by means of the trigger 21. i

c The eccentric arrangement of the locking surfaces 16 produces the effect that during the locking action the contact between the surfaces takes place smoothly and without shock, whilst on opening of the lock the surfaces move away from the cheeks of the breech block gradually and with reduced friction.

Corn `ared with other locking mechanisms, that o the present invention is distinguished by extreme reliability, its duplex arrangement, and its solidity of construction.

li claim 1. A machine gun comprising in combination: a receiver; two recoiling barrel systems slidable therein, each system containing a reciprocating barrel, a breech slide connected with the barrel, a breech-,block arranged slidably in each breech slide, a tiring pin in each breech-block, and a firing pin spring controlling the firing pin; a rocking lever connecting the two recoiling systems; a dog on each breech slide, adapted to throw over the rocking lever in consequenco of the recoiling momentum of the 'tired system; a pin provided on each breechblock, and forked ends at the rocking lever engaging the pins on the breech-blocks, so as tof-swing forward the one breech-block during the recoil of the other breechblock.

2'. A. machine gun comprising a receiver, two recoiling barrel systems slidable therein, each comprising a breech slide, a breech block, and firing mechanism, a rocking lever connecting the two systems in such a manner that recoil of one system is attended by advance or the other system, projecting cheeks on each breech block, rotary lookin discs mounted in each breech slide, said discs being adapted when in one position to enga e the projecting cheeks of the breech b ook and lock the same against the breech end of the barrel, and in another position to allow free movement of said cheeks past the discs, and means for turning the discs into breech closing and locking position at the end of the advance of the breech slide and for turning said discs into their unlocking position during the recoil ot the slide.

3. A machine gun comp-rising a receiver, two barrels adapted to recoil v therein, a

breech slide connected to each barrel, a breech block in each slide adapted to slide therein, a, firing pin in each breech block, a firing pin spring for each firing pin, a rocking lever connecting the breech blocks of the.

two systems of recoiling' parts, a dog on eachbreech slide adapted to swing over the lever at the proper times `a.n'd in such a manl ner that the recoil of one systemis attended by advance 'of the other .s stem, meansl rted to sai system by the recoil and lock the same 'against the breech end) of the barrel, and in another ition to allow free movement of said chee s past the dis'cs, and means for turning the discsinto breech closin and locking'positon' at the end of the a vance of the breech Slide and for turning said discs into their unlocking position during the recoil of the slide.

In testimony whereof I have signed my 90 name to this specification. CARL GAST. 

